Back in action, but was the Optimate to blame?
 

Gents

Thanks all for your help. Replaced the relays with a couple of new ones (for the price I didn't see the point in working out which was which) and the fuel pump whirred into life.

One worrying thing however - my *pristine* bike does not have *any* corrosion *anywhere* on it, but after leaving it connected to an Optimate for almost a year, I noticed heavy "powdery" corrosion on:

The battery mounting bracket
Parts of the regulator
One of the bellypan Dzus fasteners
Many spade connectors (including the fuel pump relay, the fuel pump power supply and the sidestand)

I can't help but think this must be some electrically-induced problem.

Any comments?

One thing to be wary of is that the process of charging a battery does give rise to acid vapours in small quantities and these can cause corrosion of the area immediately surrounding the battery unless the area is well ventilated (like when you're riding.....) This would probably account for the mounting bracket, regulator (isn't it just below the battery?), and possibly some of the other connectors). It's also possible those vapours emanated from the battery overflow (that's one of its purposes) ending up in the belly pan, possibly affecting the sidestand (not much down there that's made of metal eh!)

It's always best to take the battery out and leave in a well ventilated area when on charge for long periods. Or get a sealed battery..

New relays did the trick first time with my 916 but in the end I installed a new wire to the fuel pump due to the resistance in the existing wire (even though it was measuring 12+V) still causing it to play up. cheers

998s Fuel Pump Relay
 

Guys, thanks for your threads on this one. Just replaced the fuel pump relay (left hand black 'sugar cube' below the battery - the right one is the indicator relay) after no whirr from the fuel pump on start. Bingo! Lot of time saved and now off to IOM TT 2010!